Field of the Invention
The invention relates generally to storage and handling systems for metal fabricating materials like sheet stocks and bar stocks.
Description of Related Art
In industrial operations, metal parts and objects are formed through stamping, fabricating, spinning, slide forming and roll forming technologies, and other value-added processes. In North America, it has been estimated that the metal forming industry represents approximately $113-billion in annual sales. Raw material for metalworking processes often comprises large and bulky materials in sheet and tube and bar-stock form. When stored in large quantities, typically in the ubiquitous pallet rack or cantilever rack, the effective handling of sheet-metal and metal tubing can be burdensome and inefficient.
A pallet rack is a material handling storage aid system designed to store materials on pallets (or “skids”). Although there are many varieties of pallet rack, all types allow for the storage of palletized materials in horizontal rows with multiple levels. Forklift trucks are usually an integral part of any pallet rack system as they are usually required to place the loaded pallets onto the racks for storage. Pallet racks are an essential element of most modern warehouses, manufacturing facilities, retail centers, and other storage and distribution facilities. Nevertheless, pallet racks have certain inherent disadvantages. Disadvantages of pallet rack type storage systems include restricted access to all stock at any given moment, ineffectiveness in storing sheet-goods and other non-palletized items, and relatively high expense.
A cantilever rack allows for the safe and convenient storage of long, bulky or irregular items without an underlying pallet. Single face cantilever racks are accessed on only one side for placement against a wall; double face cantilever racks are accessible from both sides. Cantilever racks are an ideal storage solution in many situations. Compared to standard pallet racks, cantilever racks are: generally easy to use with no front column in the way; fast to load and unload; flexible in that loads may be placed anywhere along the entire length of a row on a cantilever rack; compact because the lack of a front column saves horizontal space normally lost in a rack structure; and generally more selective in that any load space is immediately accessible. Additionally, cantilever racks become more economical as load length increases. In sum, cantilever racks are especially useful for storing long, bulky, and/or oddly-shaped loads.
Despite their many advantages, cantilever racks also possess some inherent disadvantages. Chief among these are the lack of highly efficient material organization, especially when multiple material types/sizes are placed in the same rack space. Whenever multiple material types/sizes are placed in the same rack space, a worker may encounter difficulty removing materials from higher-levels. In extreme cases, a worker may even injury themselves if he or she slips while removing materials from the higher-levels. Likewise, damage might occur to nearby people or objects while removing bulky/sharp materials from any level of the typical prior art rack system. In every instance, however, the storing of multiple material types/sizes in the same rack space results in excessive worker time. Valuable worker time is consumed when a worker must first remove unwanted items in order to access buried or less-accessible materials in the rack, and then return the unwanted items before continuing with the task at hand.
Rolling sheet racks are known in the art, such as those marketed by Cisco-Eagle of Dallas, Tex. Racks of this type resemble cabinets with heavy-duty flat drawer systems that are manually extended to permit access to sheet materials or other low profile components with a crane. Prior art sheet racks, however, lack the advantages of a palletized load carrying system that can be handled by forklift truck. There is therefore a need for an improved raw material storage and handling system for large and bulky materials in sheet and tube and bar-stock form. The improved storage system preferably retains the benefits of both pallet rack and cantilever rack system, but without the burdensome and inefficient aspects of each.